Internal-combustion engine



w. wfToMPKrNs. INTERN'AVLUCOMBUSTION ENGINE. APPLICATION FILED SEPT 7| 1918- Patented Mm. 23; 1920. 3 SHEETS-SHEET I mi] M 2,3 L' j 22.

' Tag W. W. TOII/IPKINS. INTERNAL COMBUSTIOIII ENGINE.

APPLICATION FILED SEPT. ISIS.

3 SHEETS-SHEET 2.

' w,. w TOMPKINS.y INTERNAL COMBUSTION ENGINE.

APPUATION FIL'ED SEPT. r; 191s.

' Patented Mar. 23, 1920.

v Clt/tuna?? 50 stroke than the exhaust valve.

tremity with an` annular' packing 27 which may, if desired, be in the form of a piston ring. Formed on the lower extremity vof said valve is an annular reinforcingband 5 28 and projectingfrom this band at oneA y side of the cylinder is an arm 29 upon which is formed a laterally projecting trunnion 30. Engaging at one end with this' trunnion is a connecting` rod 31 formed at its l0 opposite end with a sectional eccentric strap 32 engaging around an intake eccentric uponthe shaft 13. The sleeve'valve 26, like the valve 25, is also open at its ends, being son'iewhat shorter than the latter valve. Adjacent its upper end this valve YQtis equipped with an annular packing 34 similar to the packing 27 and below this packing is formed, at opposite sides thereof, with diametric intake-ports 35,. The ports \2'0 435"are, as shown in Fig. 2, elongated to extend circumferentially of the valve and are adapted to register with the intake ports 20. In this connection it i/s to be observed t-hat' the packing'? of lthe intake valve-is of a width to overlap the intake ports 35 while the packing 34 of the ex,- haust valve is of a width to overlap the exhaust ports` 2l. Formedy on the lower end of the valve Q6 is av reinforcing-'band 36 from which projects at/ he. side of the cylthe valve 25. Eorlned on said arm, isa lateral trunn'ion which 1s connected at one end, a connecting rod 39. l Ilhis/"rod is somewhat lo'nge than the connectin'grod y 31 and. the opposite/end fthereof 'is' formed with a sectional eccentric strap 40' engaging around an exhaust'eccentric 41 upon the eccentric shaft 13.' As .particularly 40 brought out in Figs. 4 tov 7 inclusive of the Ui) than the .eccentric 41, the eccentricell leading the formereccentric by substantiallyv slxty degrees.- These eeeentrlcs are so proportioned in diameter that the exhaust; valve.

travels at two-thi1ds-tlie rate traveled by the intake valve and, of course, the' intake valve willhave a correspondingly longer llowever, fit is to be noted that the said valvesare so lcoupled with the eccentric shaft that the lintake .valve will not interfere with the niovement of the exhaust valve and will al-l 55 ways rein'ain lower than the latter valve.

The upper ends of these val vesl will therefore form a stepped wall for theA firing chamber of the working cylinder. This construction provides an arrangement whereby the facility of cooling is greatly enhanced, while, at the hottestpart of the tiring chamber of the cylinder, two thicknesses only of metal will lie between said chainber and the cooling jacket. In order that the intake ports 20 may be opened and 'fourt-hsof the cycle or during the completion of three strokes of the piston, the upper end of thejvalve will be above the ports.

'The' intake ports-35 in the exhaust valve lo are ofv a height representing .one-fourth of the-length of the stroke of this valve. However, since the ports 20 are of a height'representing somewhat more than a fourth of the length lof the stroke of the exhaust valve, 'the ports 35. will be in register with the ports 20 during an interval somewhat greater than a fourth of each. cycle of the exhaust valve. 'lheretore` even though the eccentric 41 `of the exhaust valve leads the eccentric 33'of the intake valve., the regi tration of the ports Q() and 35 will be prolonged suiiciently to permit thel intake valve,'by.reason of the fact that it travels faster than the exhaust valve, to uiufover the ports 35 while the ports 2t) and 35 are. in con'lmunication with each other. The ex haust ports 21 are also of a height representing one-fourth of the length of the stroke of the exhaust valve. so thatthese ports will thus `be opened and closed during a single stroke. ol' the piston. lfurtherniore` like the intake ports, the bottom edges of the exhaust ports 21 are located in the plane touched by the upper end of the exhaust valve when said valve reaches the bottoni of' its stroke. Consequently, these ports will Vbe open duringr the interval representing one-fourth of each cycle ol the exhaust valve. while, throughout the other threefourths of the c vele or during the comple-v tion of three strokes of the piston.v the upper end of the valve will be above the said ports. ln this connection it is to be observed that while l have. indicated that the intake. ports. .2() are of a l'ieight representing one-fourth of the length of the stroke of the intake'valve and the exhaust ports are of a height representing one-fourth of the length lof the stroke ef the exhaust valve,

.lBy referring now more particularly to Figs. S to 13 oi the drawings, it is believed that the operation of my improved engine will loe readily understood. Fig. 8 shovvs' the position ot the intake and exhaust valveso and Q6 at the upper dead center oit the piston previous' to its intake stroke. at this time the intake valve is moving downwardly while thc exhaust valve is movingupvvardly, closing `of the exhaust ports :El being preterablyoietd at iLlOOlll ve degrees after theupper dead center and opening of the intakel porta Q0 tim? 'e h the ports being effected atvabout ten' @grecs after said dead center.` In Fig. 9, the I9l= ton is shown at about onefourth Ithe down on its intake stroke. At this time the exhaust ports have, oi course, heen` clocd,

mitted over the top of the intake valvefso thatthe oaidvalvel Willzin no iva hamper the inward flow of the mixture. Iii Fig. 10, the piston is shown at the bottom of the Vintake stroke. Ait/this time;v the intake valve is moving upwardly to close the intake ports Q0. The exhaust valve Ais` also moving up ivardly hut siiioe the intake valve travels faster than. exhaust valve, the intake vulve Will overtake theexhaust valve and thus accomplishthe sealing ofthe intake ports at the proper tilndj In Fig. 1l, the

' piston is shown at the completion of the` compression stroke.' At] this time, the'eX- haust valve is moving ld'ovvnvvarlly. Hovvever, attention is directed towtle fact that theexhaust valve Well overlaps ,he exhaust ports so that the said ports are etl'e'ctually sealed for retaining tliewcompresuon of the iuel/ charge andil preventing leaklllge of the exploded gases vvhen'the Said charge is ignitcd.V ln Fig; i2, the #pistoni is shown at the bottoni of/fthc liring' stroke. At

' this time, the exl'laust valve has moved doyvn to uncover thev exhaust ports, the ,valve having `openediat "about forty-hire degrees before-the bottom dead centeryof the ring Vstroke` so that a free and unobstructed passa-ge of the burnt` gases ,from the cylndery at opposite sides thereof will be perinitted. As-in the instance' of the intake valve, the .exhaust valve will thus be loivered for discharge of the exhaust gases over the top oi the valve so that said cvliaust` valve will in no way im )ede the scavenging of the firing chamber. ton is shown at about onefourth the way up on its exhaust stroke. it this time the exhaust valve is again movino upwardly to close the exhaust ports vvhi e the'` intake valve is again moving downwardly to open the int-ak@J ports, thus completing the cycle.

It Will, therefore, be Seen that I provide `a construction wherein the sleeve valves will functionto control the intakeand exhaust of the cylinder entirely independent of the cylinder head. The necessity tor any `superstructure `upon the head. is thus eliminated and the use of a fiat head permitted. Furthermore, it will loe eeen that by employing double intake ports, free induction oi the fuel charge into the cylinder at opposite sides thereof will be permitted While, by also employing double exhaust ,silS thereof, will also he permitted;

. `llaving thus described the invention,-Wl1at ,is claimed as new 1s:

1. In engine construction, a. Working cylinder having intake and exhaust ports, a head for the cylinder, a piston mounted to reciprocate Within the cylinder, and intake and exhaust valves fitting one within the other Within'the `cylinder and surrounding said piston, the valves being open at their upper ends and slidable with respect to each other for controlling independently of the head the intake and exhaust through the open upper ends ofthe respective valves and throufrh said ports respectively.

2. Ibn engine construction, a working cylinder having intake and exhaust ports, a piston mounted to reciprocate within the cylinder, intake and exhaust valves iitting one within the other Within the cylinder and surrounding saidllpiston, the valves being slidable with resphlct to each other for con trolling the intake andrexh'aust through said ports respectively over the tops of the respective valves, and means operatively coupled with the piston for sliding said valves one at a greater speed than the other whereby the `intake valve will overtake the exhaust valve for properly closing the intake port.

3. `In engine construction, a Working cylinder having intuire and exhaust ports, a piston mounted to i reciprocate Within the cylinder, intake and exhaust valves fitting `one ilvithin the other within the cylinder and n Figa 13, the pis-V liti tive valves7 and means operatively coupled with the piston Jfor sliding the valvesl one at a greater vspeed than the other whereby the intake valve will overtake the exhaust valve and properly close the registering intake ports.

4. In engine construction, a working cylinder having intake and exhaust ports, a piston mounted t0 reciprocate within the 10 cylinder, and intake and exhaust valves slidablyiitting one within the other within the cylinder to surround the piston and movable with respect to each other for controlling the intake and exhaust through said ports respectively over the tops of the respective. valves, the-bottom edges of the intake and exhaust. rports being respectively located in a plane touched by theupperend of the intake andexhaust val-ves respectively when each of said valves is at the bottom of its stroke.

5. 'In engine construction, a working cylinde'r having intake and exhaust ports; a piston mounted to reciprocate within the cylinder, and' intake and exhaust valves fitting one within the other within the cylinder and surrounding said piston for Inovement with respect to each other to control the 'intake and exhaust through said ports respectively over the tops of the respective valves, the valves being open at their upper ends and one of the valves having its upper end constantly lower than the upper end of the other valve wherehy to provide a stepped all within t-he firing chamber of the cylinder.

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